Drill



' *nnxm' l V 1,372,257. i I I I 8peeioation-ofLettersl1ate-nt. PagtelltedldMfl'. 22, 1921. I I .application nieu september 26,1919. sei-intrisa.` :$0,503.

Toi'all fabhomz'tmayconcem: Y tremit The lower end ofthe portion is i 'Beit known that I, WILLIAM rH. Sfwnsnnn,i a citizenof the United States residing at Columbus, in the county of Iz ranklin and StateV of Ohio, have vinvented certain new and useful Improvements in Drills, of

which the following is a specification.

This invention relates to drills, and has for itsyprimary yobject to provide adrill ywith resilient means of` such character as to maintain the cutting teeth of the drill nor fmally out of contact with` the base of the kmaterial through which the drill is pene- Y trated, whereby through the use. of said resilient means, the'drill will be enabled to d eliver a clean, sharp and cutting blow to sald material so that the rongs of the tool therethrough will be considerably facilitated, and to attain these and other advantages without causing undue damage or breakage to the surroundingy portions of said material through which the drill is operating', where byfa lhole may be produced in said material fao of substantially the same proportions as the widest diameter of the cutting end of the drill.

With vthese and other objects in View, as

' will appear as .the description proceeds, the',

invention accordingly consists in theln'o'vel features of construction, combination of elements and arrangement of parts, hereinafter to be more fully described and to have the v scope ythereof pointed out in the appended claims. j

In the accompanying drawing, forming a part of this specificatiom and in which'siinilar characters of reference denote like` and corresponding parts:

Figure 1 is a side elevation of a drill constructed in accordance with the principles of the invention,

I Fig. 2 is a vertical'sectional view ltaken through the lower or cutting end of the drill, and Fig. 3 is a transverse horizontal sectional view taken along the line 3--3 ofFig. 2. y Referring more particularly `to the details of the invention, the numeral 1 designates thedrill comprising thel resent invention. This drill ma;7 beoneo several varieties,

but in'its preferred adaptation vit isl 'referably employed for cutting openings t rough marble, rock, brick or cement substances.

To -this end, the drill consistscfjaJ solid,

elongated metallic'handle portion 2and a f detachable cutting portion 3 atqits lower ex- 'exterior of the tool.

provi ed `with .the usual cutting teeth 4 and, as usual, the diameterof that portion of the tool on which. the cutting teeth are provided is appreciably larger than they diameter of the remaining portions of the tool, this beway of the space formed between the sides 'A of the opening and those vof the tool.

The lower end of the handle portion 2 is reduced and threadedas at 8, and adapted to be connected with this reduced end is a sleevelike `cutting portion 3. The upper end of the portion 3 is threaded as at 9 so as to be connected with 4the threads of the reducedend 8, and in this manner the two essential parts of the tool Vare 'capable of being securely united. Formed in the sleeve orcutting portion 3 of the toolis a spring end in a reduced in receiving bore 11, the

latter being exten ed so aS'to establish conimunication between the chamber 10 and the Slidably `mounted. within the bore 11 and disposed to extend within the chamber 10 and beyond the teeth .4 a centering pin 12. This 'p1-nis maintained 1n its operative position by providing the same with a transversely projecting cotter 13, u pon which rests a vspring seat 1li and 'a coil-spring 15 is normally interposed between the seat 14 andthe lower reduced end of the handle portion 2. By being thus confined the normal tendency of the spring its pointed outer extremity 16 will extend when the drill is relieved of pressure.

In viewV of the foregoing it will be manifest that the pin `12 will serve to maintain the cutting teethil in spaced relationship "from the face 17 -of the material through which it isv cutting, and by thus spacing said teeth, blows deliveredto the drillywill tend to force ,the teeth 4 into positive cuteo'l I lchamber 10, which terminates at its lower :sel

Y 15 `is to force .the pinr 12 outwardly so that ict ting `relationship with the face 17, said pin thus serves to enable the drill to. impart a sharp rand well defined cutting blow to the face 17 so that the maximum dutting eifort of thedrill may be produced at a concen-l trated point upon the material 7. This construction is in contradistinction to the old form of drill wherein the cutting teeth are Aconstantly maintained inr engagement with material upon which the drill is working, and in this old formi the blows delivered to the drill are also imparted to the material surrounding the same so that the opening whichvthe drillnally produces is one of a ragged character, caused by the breaking down of the material surrounding the opening through which the drill is passing. In

the present construction of the drill 1 this breaking down of the material is entirely obviated and the entire effort of the drill is concentrated only upon that portion of the material 7 through which it is passing, hence cleavage of the surrounding material is obviated. By widening the lower end of the cutting extremity 3, the space is provided for the escape of the ground or pulverized material caused by the cutting operations of the teeth 4, and this escape of material is oscillated by the compression of air caused by the downward stroke of the drill as a whole. This insures a smooth and hard face v 17 upon which the drill will operate and,

accordingly, prevents the collection of waste or cut material between the teeth 4 and the face 17. f f

What I claim is:

1. A concussion drillfor penetrating mini 4eral substances comprising a handle, cutting teeth formed upon the lower end of said handle, a pin mounted axially for sliding movement in the lower end ot' said handle, and resilient means cooperative with said pin for projecting the outer end of the same beyond Said cutting teeth.

3. A concussion drill for penetrating mineral substances, comprising a handle, cutting teeth formed with the lower end of said handle, ay pin located centrally within the lower end of said handle and arranged to be Aslidably received within a bore formed in said handle, and spring means mounted in said bore and coperatlve with said pin to normally project the outer end of the latter beyond said cutting teeth.

4. In a concussion drill, a handle having a reduced lower end, a sleeve detachably connected with the reduced end of said handle, cutting teeth formed upon the lower endyof said sleeve, a pin slidably mounted within a bore extending centrally through said sleeve, a spring confined between the re-` duced end of said handle and a fixed portion of said pin and serving to normally project the outer end of said pin beyond said cutting teeth, and said fixed part of said pin serving to limit the outward movement ot the pin.

5. In a drill of the class described. a handle of substantially uniform diameter throughout its effective length, a sleeve detachably connected with one end of said handle, said sleeve being of substantially the same diameter as said handle buthaving its lower end flared outwardly and provided with cutting teeth whose effective diameter is greater than that of the major portions of said sleeve and handle, a guide pin slidably mounted within a bore extending axially through the lower end of said sleeve. a spring positioned within said sleeve and cooperative with said pin to project the outer end of the latter beyond said cuttingr teeth, and means for limiting the outward movement of said pin said pin serving to maintain Said cutting teeth normally out ol en agement with the surface to be drilled.

n testimony -whereof I atiix my signature.

WILLIAM H. SWISHER, 

